1 /* $NetBSD: dmover_session.c,v 1.6 2011/05/14 18:24:47 jakllsch Exp $ */
2
3 /*
4 * Copyright (c) 2002 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed for the NetBSD Project by
20 * Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 * or promote products derived from this software without specific prior
23 * written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38 /*
39 * dmover_session.c: Session management functions for dmover-api.
40 */
41
42 #include <sys/cdefs.h>
43 __KERNEL_RCSID(0, "$NetBSD: dmover_session.c,v 1.6 2011/05/14 18:24:47 jakllsch Exp $");
44
45 #include <sys/param.h>
46 #include <sys/pool.h>
47 #include <sys/systm.h>
48 #include <sys/malloc.h>
49
50 #include <dev/dmover/dmovervar.h>
51
52 struct pool dmover_session_pool;
53
54 static bool initialized;
55
56 void
dmover_session_initialize(void)57 dmover_session_initialize(void)
58 {
59
60 KASSERT(initialized == false);
61
62 pool_init(&dmover_session_pool, sizeof(struct dmover_session),
63 0, 0, 0, "dmses", &pool_allocator_nointr, IPL_NONE);
64 initialized = true;
65 }
66
67 /*
68 * dmover_session_create: [client interface function]
69 *
70 * Create a dmover session.
71 */
72 int
dmover_session_create(const char * type,struct dmover_session ** dsesp)73 dmover_session_create(const char *type, struct dmover_session **dsesp)
74 {
75 struct dmover_session *dses;
76 int error;
77
78 if (__predict_false(initialized == false)) {
79 error = initialized ? false : ENXIO;
80
81 if (error)
82 return (error);
83 }
84
85 dses = pool_get(&dmover_session_pool, PR_NOWAIT);
86 if (__predict_false(dses == NULL))
87 return (ENOMEM);
88
89 /* Allocate a back-end to the session. */
90 error = dmover_backend_alloc(dses, type);
91 if (__predict_false(error)) {
92 pool_put(&dmover_session_pool, dses);
93 return (error);
94 }
95
96 TAILQ_INIT(&dses->__dses_pendreqs);
97 dses->__dses_npendreqs = 0;
98
99 *dsesp = dses;
100 return (0);
101 }
102
103 /*
104 * dmover_session_destroy: [client interface function]
105 *
106 * Tear down a dmover session.
107 */
108 void
dmover_session_destroy(struct dmover_session * dses)109 dmover_session_destroy(struct dmover_session *dses)
110 {
111
112 KASSERT(initialized == true);
113
114 /* XXX */
115 if (dses->__dses_npendreqs)
116 panic("dmover_session_destroy");
117
118 dmover_backend_release(dses);
119 pool_put(&dmover_session_pool, dses);
120 }
121